The total time taken by a boatman to travel a distance of (x+60) km dwonstream and (x-35) km upstream is 22 hours. If the boat speed and speed of stream is 15 km/hr. and 5km/hr. resp. find the time taken by the boatman to travel (x+30) km in a pond.

Downstream speed = 15+5 = 20 km/hr. Upstream speed = 15-5 = 10 km/hr. Time equation: (x+60)/20 + (x-35)/10 = 22. Solving: (x+60) + 2(x-35) = 440 → 3x - 10 = 440 → x = 150km. Pond distance = 150+30 = 180km. At 15km/hr in still water, time = 180/15 = 12 hours. However, this conflicts with checking: (150+60)/20 + (150-35)/10 = 10.5 + 11.5 = 22 hours ✓. So pond time should be 12 hours, not the claimed 12 hours which matches Option B.